This invention relates generally to ultrasonic processing of laboratory samples and, more particularly, pertains to improved sonication of samples wherein high frequency sound waves are utilized to disrupt cells in laboratory samples by vibration of a probe immersed in the sample.
It is well known to use sonicators for liquid processing, cell disruption, homogenization and emulsification of samples disposed in a test tube, beaker or the like. Such sonicators are commonly applied in manufacturing of chemicals, sonochemistry, biotechnology, preparing lipids and breaking polymers. Prior art sonicators include a signal generator for providing high voltage pulses of energy at typical frequency levels of 20 kHz. Electrical energy is transformed into mechanical energy in the form of oscillations delivered via a transducer (convertor) to a horn having an elongated probe or extender tip which is directly immersed in a sample held within a sample container such as a test tube or beaker.
In the course of using such arrangement, probes must be carefully guided by hand into test tubes and held such that the vibrating probe will not contact the sides of the test tube. In addition, each time a sample is to be processed, the sonicator must be sterilized before it is inserted into the sample in the test tube or beaker. Non-disposable sonicators are often used on bacteria which are grown with vectors to produce certain products. These bacterial cells are then disrupted to retrieve the products. Other sonicators are used on HIV infected cells, cells affected with hepatitis, etc. with the result that virulent aerosols are generated by the oscillation of the probe immersed within the sample and become airborne, contaminating the surrounding environment and placing the health of laboratory personnel at risk. In addition, the high frequency sound waves produce harmonics on the surface of the sample which result in disturbingly high noise levels. While some attempts have been made by the prior art to design sonicators which utilize fluids as an energy transmission medium and cup horns to provide ultrasonic processing without probe insertion to reduce aerosoling, there remains a need for addressing a solution which will provide a sonicator having disposable elements which reduce aerosoling, provide better noise abatement and enable self centering of the probe in each sample. Likewise, while it is known to use an acoustic enclosure for reducing continuous processing noise, it is desirable to enhance the design of a cabinet used to enclose sonication apparatus to further increase noise abatement.